Welding torch mixer



Nov. 14, 1933. R. THOMAS WELDING TORCH MIXER Original Filed Dec. 31, 1929 @6, mm No mm Mw RY /9 rfoR/VEY.

l vide a mixer having a' relatively large centralizedA Patented Nov. 14, 1933 WELDINGTORCH MIXER 'Roy Thomas, Los Angeles, Calif.

Original application December 31,' 1929, Serial' l 417,672.` Divided and 'this application Novemberv .11, 1932. SerialNo; 642,206

1 cl2-.my '(01. 15s-27.4)

This application is a division of the subjectm'atter disclosed in my coipending application Serial No. 417,672, filed December 31, 1929, yfor Welding torch mixer. v

My invention relates to torches in which a combustible gas is mixed with a combustion supporting gas, such as oxygen, so as to produce a flame of extremely high temperature which may be employed orthe fusion of metals or other 'high fusion point substances, and relates Vparticularly to a mixer for the mixing of gases employed in a torch of vthe above character.

rIt is an object of the inventiont'o provide a mixer capable of handling relatively large quantities oiV gases so 'that 'ample heat may begenerated in 'the flamefproduced `by the torch Without liability of backfire carrying 'through the torch intothe hose members through which gases Afor operation of the torch are carried.

Another object ot the invention to provide a mixer so" constructed that flash-back flames will be extinguished-thereinfso that danger of the flash-backbeing carried into the hose is avoided.

A further object of the invention is to progas passage and a surrounding oxygen 4passage having suchiormation that' hash-backy flames Will. be extinguished therein, this oxygen pasl sage being connectedwiththe gas passage in a mixer so constructed'as to extingush flash-back such a manner as toiorm jets having an injector action, YBy the use of my novel mixing construction', relatively low gas pressure may be employed, and a-perfect-mixture of the gases may be attained. n f

A further object of theinvention isto provide flames therein but being/oi` such' construction that the heat of such flashfback'fiames'is rapidly dissipatedfso as to prevent rapid heating of the mixerv parts'to such Adegree that theprei i rality of radially drilledholes 38 with an annular space 39 which is connected through an ignition of the gas mixture will take place within the mixer. j

Further objects and advantages of the invention will be made'evident' throughout the following part'cf the specification.'`

Referring'to the drawing, vwhich is 'for illus' trative purposes only:

Fig. -1 is a partly sectioned a ,Welding torch e'emplloyin'gY my new mixer.

Fig. 2i's an enlarged traginentarylongitudinalV sectionE showing the details of the mixer cone` elevational View of" [bers 13 and 14 and rwith tubes l5 and 16 within the handle 17 of the torch 10, through which tubes the oxygen and acetylene `arecarried toa head iixture 19 at the iront end of the handle. The outer. end of the xture 19 is in the form of a lthreaded projection 20 and has an outwardly diverging conical-recess21 therein adapt'- ed to receive'the plug portion 22 of Van extension member 23 forming a part of my new mixer. The extension member 23' is provided with a gas passage 24which communicates at its rearward `end with; a passage 25 in the head fixture 19' which in turn connects with the-'gas delivery tube '16. `The plug portion 220i the extension member 23v isA formed with a' counterbore 26 which is concentric with the gas passage 24.

vThe extension member 23k is threadedy at 27 so that, by means of anutv 28, a neck member,

' such as indicated at 29, may be secured thereto.`

In 'the illustration ofthe `torch I have shown a end of the member 29.'

Asbest shown in Fig. 2, the extension 23'at its point of junction with the plug portion 22 pro-v vides a shoulder 3l which constitutes the outer radial face of the' plug. The outer radial face" of the plugV is engaged by a nut32 which screws upon the threadedY portion 20 of the heady fixture 19 in such aV manner as to hold they extension member 23 in position upon said head fixture.

GFFICE A thin Walled tube or sleeve 34 having'its cir-".1

cumferential portion'turned'down to reduced diameter intermediate its ends is adapted to be 4itted within the counterbore 26. The diameter of the counterbore is of such magnitude that an 9 annular oxygen passage or space 35 is `formed'Y between the wall 36 of the counterbore 26 and the outer Wall37 ofv they tube or sleeve 34, this annular space-'being of greater length than its mean diameter, being connected through a pluoxygen passage-40 inthehea'd xture 19 with theoxygen delivery' tube "1,5 and having its for# Ward end communicating with the gas'passage 24 through radially disposed holes 41. The an# manner shown. v

yA feature of my new mixer construction is-that Athe gas passage 24 is centralized and is in alignnular space 39 is formed approximatelyhalf Vvwithin vthe conical wall 4 2 of the .plug 22 and half withinthe conical wall 430i the head fixture 19, this being 4accomplishedby (cuttingcooperatinggrooves in the walls 42 and 43 of the 'plug 22 and head xture` 19 in substantially Vthe represented by* mentwith, the gas `passage 25, this being con- Y' trary to customary construction which employsa centralized oxygen passage through which the oxygen is fed under pressure and to which flow of loxygen the combustible gas, preferably acetylene, is fed through diagonal jet openings. My new construction permits a relatively large quantity of gas to flow through thepassage 24, as indicated by the arrow 44 of Fig. 2, this gas passing through the torch structure to the `tip 30 thereof. Oxygen for supporting combustion in the gas passes through the passage 40 into the annular space 39 from whence it then passes through the plurality of holes 38 into the annular space 35 wherein it passes forward to the front end of the space 35, then passes through the jet openings 41 inwardly into the bore 45 of the tube 34 and into the flow of gas within the passage 24, intermixing therein with the gas and accomplishing an injector effect which increases the velocity of the gas and oxygen mixture toward the tip 30 of the torch. v

When flash-back occurs, the flame travels rapidly back through the necl 29 of the extension 23 to the mixer, wherein the flash-back iiame divides, a part thereof carrying rearwardly within the passage 24 and here` 45 toward the passage 25, and the remaining portion thereof carrying through the jet openings 41 into the annular space .35 wherein it is extinguished. Vhen flashback occurs, a small amount of gas is carried back from the passage 24 into the bore 45 of the tube 34 beyond the position of the oxygen openings. 41, carryingl therewith a small amount of oxygenV which rapidly intermixes with the combustible gas so that amixture is formed containing insumcient oxygen to support combustion, the result being that the portion of the ilash--backY which carries back in the passage 24 toward,

andv possibly into, the passage v25, immediately complished in what I desire to term the extinguishing space 35, due to the characteristic and peculiar formation of this space. It will be noted that the radial height or thickness of the annular space` 35, or., in other words, the distance between the outer surface of the tube 34 and the inner surface or wall of the counterbore 26, is very small. In other words, it is just sufficient to provide sufficient area for passage of all of the oxygen which maybe forced under pressure through the jet openings 41. It will be recognized, therefore, thatthe radial height of the passage 35 may be made'considerably less than the diameter of the openingsfll and yet maintain therein an area of cross-section equal to the cumulative-area of theV openings 41. It is believed that when the oxygen side of the flash-back flame enters the space 35, it is vflattenedV out in` the small space thereby provided, and its heat is absorbed by the large area of wall surface presented to the space 35, the result being `that the combustion cannot be then further supported. l

By havingthe jet openings 41 lead `from an oxygen passage of relatively small height clr thickness and of correspondingly large width, I am enabled to form a passage through which combustion will not carry, in this manner effectually extinguishing hash-back which might otherwise carry into the oxygen passages of the torch and into the oxygen hose member 13.

The extension 23 and the tube 34 are preferably constructed ofV copper. The heat of the flashback is very quickly dissipated through the plug portion 22 of the extension 23 which surrounds the counterbore 26 and those portions of the head fixture 19 with which it engages. The rapid dissipation of heat due to this construction prevents heating of the mixing structure to such a degree that the pre-ignition will take place in the torch. Therefore, by use of my new mixer I am enabledto substantially eliminate the very undesirable rapid nre-back action encountered in the use of many welding torches of standard construction.

VIn these illustrations I have shown preferred proportions of the extinguishing passage 35 and the openings 41 and 38. These proportions may be varied within reasonable limits to suit the pressure and quantity of oxygen 'necessary to produce perfect combustion of the combustible gas employed by the torch. For instance, in torches of extremely large size, the central passagel 24 will be increased and the mean diameter of the extinguishing passage 3,5` will likewise be increased so that a corresponding increase in area may be obtained therein. The length of the passage 35 and its thickness may also be varied in accordance with existing conditions without departing from the valuable features of construction of the invention. Y i Y In this form of the invention radialjet open,- ings 41 are shown'conimunicating betweenl the extinguisrahingl passage 35 and the passage 2,4, it being found that the'non-flashback characteristics of my new construction are not affected by the angle at which the vjet o-penings 41 or the openings 38 are drilled.

Although I have herein shown ,myy invention in simple and practical form, it is recognized thatv certain parts or elements thereof are representa-f tive of other parts, elements, or mechanisms, which may be employed in substantially the same manner to accomplish substantially theV same result; therefore it is to be understood that the invention is not to be limited to the details disy closed herein but shall have the scope of the following claim. Y

I claim as my invention: Y

A mixer construction for use with a torch handle having a recess in one end, including: a mem. ber having a gas passage therethrough and a taperedportion seating against the wall of saidl recess; securing means connected to said torch handle and retaining said tapered portion o-f said member in said recess; and an inner memberhaving a gas passage therethrough and having enlarged end portions, `said inner member being disposed in said gas passage of said memberso as 1351 to define between said enlarged end portions and between said inner member and the Wall of said gas passage in saidmember an oxygen chamber of small radial thickness and greater length-for the extinguishment of flash-back flame, said 14a,

member having an oxygen delivery passage con--4 necting one part of said oxygen chamberto an` oxygen source, and said inner 'member' having jet openings connecting another part of said oxygen chamber to said gas passage.

` ROY THOMAS. 

